Wireless communications networks are widely deployed to provide various communication services such as voice, video, packet data, messaging, broadcast, and the like. These wireless networks may be multiple-access networks capable of supporting multiple users by sharing the available network resources.
A wireless communications network may include a number of access points. The access points of a cellular network may include a number of base stations, such as NodeBs (NBs) or evolved NodeBs (eNBs). The access points of a wireless local area network (WLAN) may include a number of WLAN access points, such as WiFi nodes. Each access point may support communication for a number of user equipments (UEs) and may often communicate with multiple UEs at the same time. Similarly, each UE may communicate with a number of access points, and may sometimes communicate with multiple access points and/or access points employing different access technologies. An access point may communicate with a UE via downlink and uplink. The downlink (or forward link) refers to the communication link from the access point to the UE, and the uplink (or reverse link) refers to the communication link from the UE to the access point.
As cellular networks become more congested, operators are beginning to look at ways to increase capacity. One approach may include the use of WLANs to offload some of the traffic and/or signaling of a cellular network. WLANs (or WiFi networks) are attractive because, unlike cellular networks that operate in a licensed spectrum, WiFi networks generally operate in an unlicensed spectrum. However, the use of unlicensed spectrum by both cellular and WiFi devices may require the use of a contention-based protocol to gain access to the unlicensed spectrum. Thus, devices wanting to communicate over the unlicensed spectrum over multiple data frames may have to account for transmission gaps between data frames (e.g., gaps caused by other devices capturing the unlicensed spectrum and preventing the devices from communicating over the unlicensed spectrum during multiple adjacent data frames).